Lubricating oil additives



a Wide variety of lubricating oils.

contains a longchainof carbon atoms. also contemplated to use unsaturated 111G251- Patented Feb. 20, 1951 UNITED STATES PATENT 0mm;

Samuel B. Lippincottand IzuuisaLMikeska, :Westfield, N. J assignors to Standard Oil Development Company, a corporation of-Delaware No Drawing. Application August 2, 1948, .Serial No. 42,154

1 Claim.

1 This invention relates to novel "chemical 'copolymer products and to processes for preparing and using the same. It relates further to oil-compositionscontaining such products. More particularly it relates to high molecular ,weight copolymers of unsaturated dibasic acids and their derivatives with other olefinic substances and also to their use inoilcompositions as lubricants and the .like. These novel .copolymers are especially usable for improving the pour point, viscosity index, and other properties .of mineral base lubricating oilsand the like.

One object of the present inventionis thep'roduction of pour depressants of high potency in Another object is to produce .pour depressants'h'aying good pour stability under conditions of winter field storage. A furtherobjectis the production of a good lubricating oil additive which not only lowers the pour point but also increases the viscosity index of the oil so that theadditive is not only a good pour depressant when used "in small amounts but will also be anefiective pour .de-,

pressant when used inlhigher concentrations as a viscosity "index *improver. The utility -of the invention is not limted to hydrocarbon oils as the'improved copolymers are .useful alsotin synthetic'oils and related products.

Broadly, the present invention comprises the production of copolymers of 'ethyIene-LQ-dicarboxylic acids and'their derivatives such as 'maleic acid, fumaric acid, .citraconic acid, mesaconic acid, glutaconic acid and'the like, their anhydr' ides, or other derivatives and an olefin that It is boxylic 'a'cids where the double bond ih-asr-moved from the 1,2 position,for example,:itaconic acid.

'The olefin compound usable in the .copolymerization with maleic acid and itsderivatives :are ordinary olefins 'containingtfromi-tlito -2 iistraight chain carbon atoms. Among these olefinic materials are octene, decene, dodecene, hexadecene,

octadeeene and the like.

.such as by blowing the reaction mixture or the provement is the primary object. plated "that the copolymers may be used directly or maybe neutralized by forming -a metallic, ammonium-or amidesalt of the-copol ymer. The

oil base stocks in -='which the cepQIy mers may be used may range from pa'raiimic oil's which re- 3 quire pour depressants, naphthehic or mixed lubricating oils which are "to be imp'ro'ved with re-- spect to viscosity index. Synthetic oils also may be improved by the product of this invention..

The copolymers :may also &be used in greases which contain metal salts or in parafiin wax or waxy compositions or inlighter liquidhydrocarbon oil products such as Diesel fuel .base stock which are oftenihigher parafiinic immature and require .pour depressants or .other. additive :material to facilitate their use. Copolymers may be used with other light oils such as domestic heating oil base stock, mineralfseal oil, refined kerosene and th -like. ltis also contemplated that certain of these copol-ymers -may --be used directly as lubricating oils in.,their.own right.

In preparing the lubricating oils or other com- :positions containing thenovel 'copolymers-bf this -invention,.one may alsoadd otherconventional additives such as dyes, .antie'oxidants, -:or.oth-er .types ofpour depressants such asthe wax-:naphthalene condensationproductin common com"- mercial use p as .well as other viscosity index improvers such as polybute'ne, polyacrylates, and the *like.

The invention will be betterunderst'oodfrom a consideration of the following examples:

EXAMPLE 1 and the product was then concentrated further by heating to 200 C. at 1-2 mm. pressure. The resulting product (150 g.) was a brittle glass-like resin, light yellow in color. Analyses (73.40% C, 10.31% H) indicated that the copolymer was made up of maleic anhydride units and octadecene units i a molar ratio of about 1.25. It was blended with Test 011 A and the following pour point data were obtained. Test oil A is a solvent extracted Mid-Continent neutral plus 3 5% Pennsylvania Bright Stock having an SAE grade of 10. Test oil B is a solvent extracted Mid-Continent neutral having an SAE grade of 10. The S. O. D. Pour Stability test is described in the Transaction of the Society of Automotive Engineers, vol. II, No. 1 pp. 34-44.

TABLE I A. S. T. M. S. 0. 1). Pour Sta.- Conc" Pour Point, bility Cycle A, 9 F. Solid Point, F.

EXAMPLE 2 The experiment of Example 1 was repeated using a mol ratio of olefin to maleic anhydride of 2 instead of 1. The product (165 g.) was very much like that obtained in Example 1. The carbon and hydrogen content of the copolymer (74.34% C, 11.04% H) indicates that the two monomers copolym'erized at a molar ratio of 1.

TABLE II In test oil A A. s. T. M. Pour Point, F.

S. 0. D. Pour Stability Cycle A, Solid Point, F.

00110., Per

ent

F999 ommw EXAIWPLE 3 TABLE III In test oil A A. S. T. M. S. O. D. Pour Sta- Pour Point, bility Cycle A, en T. Solid Point, r.

EXAMPLE 4 Example 1 was repeated using chloroform as the solvent. This resulted in a lower temperature of reaction (67-75 C.) Refiuxing was con tinued for four hours after the addition of the catalyst had been completed.

The product (126 g.) was dark brown. The analyses (73.10% C 10.46% H) indicated a copolymer in which the molar ratio of maleic anhydride units to octadecene units was about 1.25. Blends in lubricating oils gave the following results:

TABLE IV In Test 011 A Test 011 B, C t A S T M 511311" 5 3 i '1 t one. per cen i y yc e o t.

F- A, Solid 1%., F.

Example 2 was repeated using chloroform as the solvent. The product g.) was a light brow viscous fluid. The analyses (75.01% C, 10.01% H) indicates the maleic anhydride and octadecene copolymerized at a molar ratio of about 1.2.

The product was blended with lubricating oil and the following pour point data were obtained:

Example 1 was repeated using ethyl ether (350 ml.) as the solvent. The reaction temperature was 42 C. Refiuxing was continued 20 hours after the catalyst had been added. The product (107 g.) was a reddish-brown brittle solid. Analyses (75.15% C, 11.60% H) indicated that the maleic anhydride and octadecene copolymerized at a molar ratio of about 1.3.

TABLE VI In Test Oil A S. O. D. Pour A S. T M Conc. per cent Stability Cycle A, Solid Pt., F.

O 0.05 +30 0 0. 1 +30 20 Q2 0. 25 1O 0. 5 -25 l. O 25 weenie nxainplez'was'repeatedusin ether (6'00 n11.)

as the sdlv'ent. Refluxing was continued for twenty hours after the completion of the catal'ys't'ad'dition. Theproduct (.148 g.) was "a brittle amber colored solid. 'The analyses (74.16% C, If8'7% H) indicated that the "maleic 'anhydride and octade'cene cop'olymeri'zed "in a molar ratio or about 1.1.

A flask was charged with 49 g. of maleic anhydride, 126 g. of octadeeene, 155 ml. of benzene and 0.09 of ferric laurate.v Two solutions were prepared, one by dissolving 3 'gfdf benzoyl peroxide in 60 m1. of benzene and theother by dissolving 3.7 g. of benzoin in 60 ml. of benzene. The flask was heated to boiling and ml. ofeach of the two solutions were added. Each hour another 10 ml. of benzoln solution and 10ml. of benzoyl peroxide were added until all had been added. Re'fluxing was continued for an hour after the addition of catalyst had been completed. Solvent was removed by heating the product to 200 C. at atmospheric pressure and then to the same temperature at 1 2 mm. pressure. The product (118 g.) was a :brown brittle solid. Analyses 71.76% C and 10.15% H) indicated that the maleic anhydride and octa'decene copolymerized at -:a molar ratio of about 1:4.

The product was blended with lubricating oils and the following pour point'data lwere obta-ined:

Experiment 1 was repeated using lhexadecene in place of the l-octadecene. The residue was an amber colored brittle solid. Analyses (72.58%

Example 1 was repeated using l-tetradecene in place of l-octadecene. The product (127 g.)

was a ibrittle amber colored :soli'd. Analyses 671.28% =G, 33.52% indicated that the maleic anhydride :and =tetradecene copolymerized at a molar ratio of about 1.3. The product iivas found to be soluble in Test oil but "did not lower the incur point when :pr'esent 'to the extent of 1 However, it mig-ht impart other "beneficial pro erties to the veil such as detergents and it can she converted to a pour "depressant by esterification, etc.

"""L'Ell Example 1 was repeated using l-dodec'ene :in place of the l-octadecene. The product (118 g.) was a brittle solid at room temperature. Analyses (7"2198% C, 'I'0f29% Tl) "indicated that the maleic :anhydride and dodecene copolymerized at a molar ratio of about 0.9. The product was not soluble in Test oil "At'othe extent of 1%.

EXAMPLE 12 Example .1 was repeated using 7 l-decene in place of the l-octa'decene. The product g.)

was a brittle, light'ambercoloredsolid. Analyses (71.83% C, 9.82% H) indicated that the maleic anhydride and decene copolyrnerized at a molar ratio or abet-00:0. The product was onlyslig htly soluble, less than 1%, Test oil A.

Qitracoh-ic :anhydride 656 'g.')., .l-octadecene (126%.) and benzene G200 'cc.) were-mixed ina 'flask and healted tc refluxing. IBen'zoyl peroxide -O1' /2 g.) ifn benzene (30 en) was added in six :edual p'or tions at hourly intervals while the rim:- ture was maintained at-the hoi ling temperature. The mixture was allowed to reflux for :1- hours after "the last portion of catalysts was added. Benzene was then removed by distillation, heatingito a-potternperature 6f200 G. Distillation was continued at'redu'ced pressure finally heating to 200 C. at 1 to-2 min. pressure. The residue 16.31%.) was a 'viscousyclear, amber colored fluid that became quite solid .at room "temperature. :It was blended with lubricating oil and the F tollowing data were o'btained.

TABLE Blends lubricating oil In one. v In 28 11 0111 Pea... m o +30 +5 +30 -15 +30 -25 1 -30 -25 ItaconicIacid (65 g.) ,'1-octadecene'(126 g.) and benzene (700 cc.) were mixed in a flask and refluxed. The itaconic acid did not completely dissolve. .Benzoy'l peroxide (l g.) was dissolved in benzene (30 cc.) and thesolution was added to the boiling reaction vmixture in six equal portions "at hourlyintervals. 'Ther'efluxin'gwascontinued for an "hour after the last addition 'of catalyst. -Upon cooling considerable precipitate separated.

This was filtered off, washed with benzene and air dried. The white solid (64 g.) was found to be unchanged itaconic acid. The filtrate was concentrated by distillation heating to 200 at 1-2 mm. pressure. The distillate (121 g.) was Blends in lubricating oil In Oil A Pour Per Cent Pt, F.

EXAMPLE 15 Itaconic anhydride (56 g.), l-octadecene (126 g.) and benzene (200 cc.) were mixed in a flask and heated to refluxing. Benzoyl peroxide (1 /2 g.) was dissolved in benzene (30 cc.) and then was added to the refluxing mixture in six equal portions at hourly intervals. Refluxing was continued for one hour after the last addition of catalyst. A precipitate separated during the reaction period. After cooling, the mixture was filtered and the precipitate was washed with benzene and air dried. It was a white powder (42 g.) that did not melt at 200 C. Analyses (58.03% C, 5.40% H) indicated that this product is a copolymer of itaconic anhydride and l-octadecene in a mol ratio of about 14:1, i. e., predominantly polyitaconic anhydride.

The filtrate was concentrated by distillation finally heating to 200 at 1-2 mm. pressure. Considerable octadecene (103 g.) was recovered as a distillate. The residue (40 g.) was an amber colored brittle solid. Analyses (C=73.07%, H=l0.68%) indicated that this product is a copolymer in which'the' mol ratio of the monomers, itaconic anhydride and octadecene, is 1.5. This product was oil soluble and has properties of a pour depressant as indicated below.

Tzuam: XI Blends in lubricating oil In Oil A In g il B Flour t Conc. Per 3,. Pour Pt., F.

EXAMPLE 1'6 Chloromaleic anhydride (66.3 g.) l-octadecene (126 g.) and benzene (100 ml.) were heated to boiling (105 C.). Benzoyl peroxide (1 g.) was dissolved in benzene (30 ml.) and the solution was added to the refluxing mixture in six equal portions at hourly intervals. Refluxing was continued for one hour after the last addition, then benzene was distilled until the pot temperature reached 160 C. The product was concentrated further by heating to 200 C. at 1-2 mm. pressure. There was evidence of some hydrogen chloride splitting out at this temperature. The residue (134 g.) was an amber colored viscous fluid. Analyses of the product follow.

Calculated for Found 221137 0301 o=7s 157 C=68.63 H=10 01% H= 9.69 o1= 4 13% o1= 9. 21

The low chlorine is due, no doubt, to the decomposition during the isolation of the product as mentioned above. The product was blended with lubricating oils and the following data were obtained:

It is further within the contemplation of the invention that the copolymers may be neutralized by reacting with an alcohol, a primary or secondary amine or with a metal to obtain an esterified, amidized or imidized product or a metallic salt.

What is claimed is:

A composition consisting essentially of a major proportion of an oil base stock and from 0.01 to 10% by weight of a product consisting essentially of a copolymer of maleic anhydride and octadecena'said copolymer being formed by condensing from l'to 4mo1s oi the said octadecene with 1 mol of the said anhydride in the presence of 'benzoyl peroxide catalyst at a temperature of from C. to 200 C. at atmospheric pressure.

SAMUEL'B. LIPPINCOTT. LOUIS A. MIKESKA.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,055,456 Eichwald Sept. 22, 1936 2,133,734 Moser Oct. 18, 1938 2,168,535 Nusslein Aug. 8, 1939 2,366,517 Gleason Jan. 2, 1945 2,370,943 Dietrich Mar. 6, 1945 2,378,629 Hanford June 19, 1945 2,380,304 Gleason July 10, 1945 2,422,278 Young June 17, 1947 

